Derivatives of 3-nitro-4-hydroxy-benzamide



Patented Sept. 26, 1933 UNITED STATES DERIVATIVES OF 3.-NITRO-4HYDROXY BENZAMIDE Winfricl Hentrich, Leverkusen-Wiesdorf, Richard Stroebel, Opladen, and Ernst Tictze, Cologne; Germany, assignors to General Aniline Works, Inc., New York, N. Y., a corporation of Delaware N Drawing. Application August 29, 1930, Serial No. 478,780, and in Germany September- 11,

Claims. (Cl. 260-424) The present invention relates to new derivatives of 3-nitroi-hydroxybenzamide, more particularly it relates to compounds of the probable general formula:

wherein ac stands for hydrogen or an alkyl group, R. stands for an aromatic nucleus, y stands for an amino-, nitro-, hydroXy-group or for the group N=N R1 meaning an aromatic nucleus, and

wherein all nuceli may be further substituted, for

example, by sulionic and carboxylic acid groups,

alkyl, alkoxy, hydroxyl, the nitro and amino groups.

Our new products are obtainable by causing a 3-nitro-4-acylhydroxy-benzoic acid halide:

(JO-Hal OAc (Ac=acyl residue, for example, CI-IaCO,

ganic solvents alone, acid binding agents, such as sodium acetate, sodium carbonate, magnesium oxide, tertiary bases, such as pyridine or dimethylaniline being added, as and when desired.

The condensations proceed very smoothly.

Already during the reaction a complete splitting off of the O-acyl group takes place.

Our new compounds are colorless to greenish to brown crystalline substances and are valuable intermediate products in the manufacture of a nitro-acylhydroXy-' By treating the new o-nitro-hydroxy compounds thus produced with reducing agents, 0- aminchydroxy compounds are obtained, which contain the o-aminophenol grouping inthe external position besides containing the azo group or groups capable of azo dyestuff formation respectively.

The following examples illustrate our invention, without limiting it thereto, the parts being by weight: 7

Example 1.l8,8 parts of 1.3-phenylenediamine-i-sulfonic acid are dissolved in 500 parts of water with the addition of sodium carbonate to form a neutral solution. The solution is heated to 40 C., 30 parts of crystalline sodium acetate are added and 2423 parts of l-acetoxy-3-nitro-' benzoyl chloride (this compound, hitherto unknown, is obtainable by the interaction of 3-nitro- 4-acetoxybenzoic acid with thionyl-chloride'; a colorless crystalline mass, melting at C.) are introduced with brisk stirring. The mixture is then heated quickly to C. and stirred for a further half hour at this temperature; the 4- acetoxy3-nitrobenzoyl chloride thereby quickly disappears and the solution is coloreda deep yellow. On cooling the reaction product of the formula:

HOsS

IIqHQ N02 is precipitated by means of dilute hydrochloric acid and filtered by suction. After the customary working up, the new compound is obtained as an almost colorless powder, which dissolves in sodium carbonate solution with a deep yellow coloration and is capable of being diazotiz ed. By, the reduction of this compound, for example,fwithv iron and acetic acid, the corresponding diamino compound is obtained.

In an analogous manner a condensation product possessing similar properties is obtained by causing interaction with a-acetyloxy 3-nitrobenzoyl chloride of lA-phenylenediainine-Z-sulfonic acid instead 'of the 1.3 phenylenediaminel-sulfonic acid. The'compound of the formula:

cool

N02 (Journ. Chem. Soo.'127 2646) )oooozH5 canlikewise be employed with similar results instead of the 3,-nitro-4-acetoxybenzoyl chloride.

When in a similar manner B-nitrol-acetoxy benzoyl chloride is caused to react with the sodium salt of 2.5-diaminol'-hydro: ;y-l.l-diphenylsulfone-3-carboxylic. acid or with the I i NHg 0H p are thus obtained.

Example 2.31.9 parts of 1-arnino-8-naphthol-3.6disulfonic acid are covered with 500 parts of water and caused to dissolve by the addition of 10.6 parts of calcined sodium carbonate. After the addition of 30, parts of, crystalline sodium acetate, 24.3 parts of 4-acetoXy-3-nitrobenzoyl chloride are introduced at 40 C. with brislr'stirring; the mixture is quickly heated to C. and stirred for a further half, hour at this tempera ture. The solution thereby acquires a strong yellow coloration and assumes acid reaction to litmus. On cooling the resulting condensation product of the following formula:

to the process described above by employing-in stead of l-amino-8-naphthol-3.6-disulfonic acid the 2-amino-5-naphthol-7-sulfonic acid, the 2- amino-8-naphthol-6-sulfonic acid or the 1- amino-8-naphtho1-4-sulfonic acid.

The reaction of secondary amines takes place as follows: 1

As an example, 34,7 parts of l-ethyl -amino-8- naphthol-3.6-d-isulfonic acid are dissolved to a neutral solution by means of the corresponding quantity of sodium carbonate, 30 parts of crystallized sodium acetate are added and 24.3 parts of 4-acetoXy-3-nitrobenzoylchloride are then introduced at 50 C. with good stirring. The mixture is heated for a further half hour at 601 C.

and is then allowed to cool. The condensation product formed is very readily soluble, it is isoilated by evaporation of the weakly acid solution,

I and which has th Aininobenzoylated arninonaphthol sulfonic acids or in general aminonaphtholsulfonic acids, containing reactive amino groups in the heteronuclear side chains can likewise be causedto sodium salt of 4.4.-diaminodiphenyl-3-sulfonic react readily WW9 LaCYIOXYWSmitmhenzoyl acid, the respective condensation products preh do 1 W 1 f f 3 cipitate even during the reaction as difficultly ekampe, 1 f Soluble precipitates and in a pure state (303cmv nltrobenzoyl chloride and 2-(3 -am1nooenzoy1) pounds of the formulae; aminoE-naphthol-Y-sulionic acid, a condensa- 1| IOa V I| I0z 1 IE-'oo -oH NHCOOOH NH I 7 and tion product is obtained which separates well e following constitution:

Earample parts of 2-nitro-4-aminophenol-fieculfonic acid are dissolved in 500 com. of water to a neutral solution with the addition of sodium carbonate, 36 parts of crystalline sodium acetate are added and 24.3 parts of l-acetoxy-3-nitrobenzoyl chloride are introduced in one addition at 45 C. with brisk stirring. The liquid is at once colored deep yellow and lustrous gold colored plates soon separate; very quickly and particularly, when heating for a short time to 60 C., they extend throughout the whole contents of the vessel in the form of a thick magma. Stirring is continued for a further half hour at 80 C. and the new product is then filtered by suction. The condensation'product' thus obtained is already completely pure. It dissolves with a deep yellow coloration in dilute sodium carbonate solution and no longer reacts with nitrous acid.

In an analogous manner proceeds the manufacture or" the condensation product from 4-acetoxy-EE-nitrobenzoyl chloride and .2-hydroXy-3- nitro-5-arninobenzoic acid. A yellowish brown powder is obtained, which dissolves readily in water in the presence of sodium carbonate and is indifferent towards nitrous acid.

When it is intended to condense an amino'135 compound, which is insoluble in sodium carbonate, with a l-acyloxy-3-nitrobenzcyl halide an organic solvent is with advantage employed for theprocess. For example, the compound of the 15.2 parts of 2-nitro-4-toluidine are dissolved in 400 parts of dry benzene, 10 parts of pyridine are added to combine with the hydrogen chloride formed during the reaction and a solution of 24.3 parts of l-acetoXy-3-nitrobenzoyl chloride in 100 parts of benzene is slowly dropped in at 5-10 C. with good stirring. As soon as this addition is complete heating is slowly eifected at 60 C. A heavy brown oil thus separates, from which on cooling of the reaction mixture the benzene is separated. The oil obtained is triturated with methyl alcohol, in which it 'is partly soluble; After evaporation of the resulting suspension the desired condensation product is obtained as a fine powder, which can be recrystallized from xylene. It forms long, greenish yellow needles, which melt at 221-222 C.

Instead of pyridine other tertiary bases, such as dimethylaniline, can likewise be employed as acid binding agents.

Example 4.-18.0 parts 'of l-oxalylamino-3- amino-benzene are dissolved in 800 parts of cold water to'a neutral solution by the addition of sodium carbonate and 30 parts of crystalline sodium acetate added to the solution thus prepared. The solution is heated to 40 C. and 24.3 parts of 4-acetoXy-3-nitrobenzoyl chloride then introduced in one portion with brisk stirring. The latter completely disappears in the course of a quarter. of an hour and a clear solution is produced, from which microscopic, pale yellow needles separate after standing for 12 hours; these dissolve in sodium carbonate solution with a yellow coloration and cannot diazotized. The splitting off of the oxalyl residue takes place readily with alkaline agents according to the customary processes. when a diazotizable com pound is obtained, which couples with R-salt to a readily soluble yellowish red azo dyestuil. By reduction of the aniino-nitro compound thus obtained, a compound results of the constitution:

i yoz nonsoin (described in Example 2) in 260 parts of water, to which have been added 10 parts of an aqueous caustic soda lye of 30% strength. As soon as all the solution has been added, heating is effected to 60 C. and it is maintained for some time at this temperature. 7 On cooling and after acidifying, a thick magma is formed, which is filtered by suction and taken up in dilute sodium carbonate solution. The sulfur suspended in the solution is filtered oil. The clear filtrate is acidilied and the desired reduction product is thus obtained as a thick magma, which'is filtered by suction and dried. The new compound reacts'with nitrous acid to give a yellow colored solution.

Example 6.-l.{l condensation product obtainable according to Example 2 from 3-nitroacetoxybenzoyl chlo-- ride and *2-amino-5-hydroxynaphthalene-7-sulfonic acid are dissolved in 490 parts of hotwater. After the addition of 10 parts of an aqueous acetic acid of 30% strength 20 parts of iron filings are added to the boiling solution, which is kept boilfora further short time. The reduction is completed very quickly; the end point is ascertained when on spotting a test portion on filter paper with sodium carbonate solution a yellow coloration no longer appears. A solution of 5 parts of sodium carbonate is now added and the mixture filtered by suction. The2-(3'-aminolhydroxybenzoylaminol-B hydroxynaphtha lene-V-sulionic acid is separated quantitatively from the cooled, slightly brownish filtrate by the.

the action of reducing agents.

Example 7.-l5.3 parts of 5-amino-2-hydroXy-, benzoic acid are dissolved in 500 parts of water with the addition or sodium carbonateto forma neutral solution. ,To this are added 30' parts of crystallized sodium acetate and with brisk stirring and heating to 5G 0. 12%.3 parts of parts of the sodium salt of the 10o described inthe above troduced into the solution. After heatingfor a:

short time to 65 C. the reaction is complete, this being recognized when the solution obtained no longer reacts withnitrous acid. ,The liquid is allowed to cool andthe reaction product is pre-' cipitated'with dilute hydrochloric acid. After working up in the customary manner, it is obtainedin the form of a weakly greenish colored powder, which dissolves in dilute sodium carbonate solution with a deep yellow coloration and cannotbe diazotized. The new compound cor-.

responds to the formula:

no; I 30011 I In an analogous manner'condensation products possessing similar properties are obtained by employing instead of 5-amino-2-hydroXybenzoic acid the 5-amino-3-methyl-2-hydroxybenzoic acid, 3-sulfonic acid-5-amino-2-hydroxy benzoic acid or 5-( l-aminobenzoyl)-amino-3-sulfonic acid-2-hydroxybenzoic acid with 3-nitro-4acethydroxybenzoyl chloride or other 3-nitrol-acylhydroXy-benzoic acid halides.

Condensation products of this kind are converted by reduction into valuable diazotizing components; for example, 31 parts of the contion. The solution is boiled, 30 parts of 30% acetic acid are added, then 60 parts of iron filings are introduced and the liquid is heated for a short powder, dificultly soluble in water and forms a yellow diazo compound, which dissolves with difficulty.

In an analogous manner all the other condensation products produced from substituted aminoo-hydroxybenzoic acids and 3-nitro-4-acylhydroxybenzoyl chlorides, mentioned in the example, can be converted into the corresponding amino compounds.

Example 8.-25.7 parts of the azo dyestuff H 4-amino-4-hydroxy azo benzenaW-carboxylic yellowish brown precipitate. dissolved in 300 parts of water by means of 2 thydroxy compounds.

' acid are dissolved to a neutral solution in 700 parts of water with the addition of sodium carbonate, parts of crystallized sodium acetate are addedand 24.3 parts of l-acetoxy-3-nitrobenzoyl chloride are introduced quickly with vigorous stirring into the solution heated to a temperature of C.

The reaction begins immediately and the re-- action product separates in a pure form as a 10 parts of this are partsofsodium carbonate and heated to 40 C. To this is added a concentrated solution of 26 parts of crystallized sodium sulfide and the whole is further heated quickly to C. and stirred for half an hour longer at this temperature. After cooling the solution is acidified with dilute hydrochloric acid, the precipitate produced is filtered off with suction and dissolved in dilute sodium carbonate solution. The sulfur suspend- 'ed in the solution is removed by filtration and the light yellow. reactionproduct is separated from the filtrate by means of sodium chloride, filtered and dried; Thus is obtained 4-(3"-amino-4"- hydroxybenzoyl) an1ino-4J- hydroXya-zobenzene- 3 -carboxylic acid.

In an analogous manner other aminoazo compounds, for example, that from diazotized Z-amino-naphthalene-l.8-disulfonic acid and 2-amino-1.4-dirnethylbenzene can also be caused to react with 3-nitro-4=acetoxybenzoyl chloride or other 3-nitro4-acyl-hydroxybenzoic acid halides and the o-nitro-hydroxy compounds produced be reduced to the corresponding o-amino- We claim:

1. As new products compounds of the probable general formula:

' general formula: 1

wherein R stands for an aromatic nucleus, and wherein all nuclei may be further substituted by substituents selected from the group consisting of alkyl, alkoxy, hydroxyl, the nitro-, aminosulfonic acidand carboxylic acid group being generally colorless to greenish to brown crystalline substances and being valuable intermediate products in the manufacture of dyestuffs.

3, As a new product the compound of the following formula: v

I NHz N02 being an almost colorless powderwhichdissolves in sodium carbonate solution with a deep yellow coloration and being capable of being diazotized.

4. As a new product the compound of the following formula;

not

HQ3S -SO3H being a yellow powder and being a valuable inter-" mediate product in the manufacture of dyestufis. 5 As a newproduct the compound of the following formula:

i voz coon being a weakly greenish colored powder and being a valuable intermediate product in the manufacture of dyestuffs. E40 WINFRID HENTRICH.

RICHARD STROEBEL. ERNST TIETZE. 

